KR20040064648A - System and method for controlling distribution traffic in mobile communication system - Google Patents

Abstract

PURPOSE: A system and method for distributively controlling traffic in a mobile communication system are provided to effectively control a mobile terminal in handover and a mobile terminal not in handover. CONSTITUTION: Uplink control function parts(201-20N) control uplink transmission rate of a Non-SHO(Soft Hand Over) mobile terminal. A control function part(210) of a BSC(Base Station Controller) controls base stations that has been performed up to now and controls an uplink transmission rate of a SHO(Soft Hand Over) mobile terminal. The control function part(210) checks whether allocation of a new transmission rate control channel is necessary and at the same time checks whether allocation of an ACK channel is necessary. When a mobile terminal in handover enters into a specific base station, the control function part(210) instructs each corresponding base station control function part(201-20N) to which the mobile terminal belongs to individually control the uplink transmission rate of the mobile terminal.

Description

Traffic distribution control system and method in mobile communication system {SYSTEM AND METHOD FOR CONTROLLING DISTRIBUTION TRAFFIC IN MOBILE COMMUNICATION SYSTEM}

The present invention relates to a traffic control system and method in a mobile communication system, and more particularly, to a control system and method for reverse traffic.

In general, data transmission may be classified into a forward data transmission and a reverse data transmission in a mobile communication system. Here, forward data transmission means data transmission from the base station to the mobile terminal, and reverse data transmission means data transmission from the mobile terminal to the base station. In addition, according to the data transmitted from the mobile communication system, it can be divided into a type that supports only voice service, a type that supports both voice service and simple data service, and a type that supports only high-speed data service. The emergence of a mobile communication system that provides data services is a result of the rapid development of mobile communication technology in response to the desire for users to transmit and receive more information faster.

As described above, data transmission in the reverse direction is transmitted through a packet data channel in units of physical layer packets (PLP) in a mobile communication system that processes high-speed data, and a packet length is fixed. The data rate of the packet varies from packet to packet, and the data rate of each packet is the power rate of the terminal, the amount of data to be transmitted, and the rate control information (RCB: Rate Control Channel) transmitted from the base station through a data rate control channel (RCCH). Control Bit).

In addition, the data rate of the mobile terminal is achieved by scheduling. The base station performs scheduling using a rise over thermal (RoT) representing total received power to thermal noise, or a load obtained from a received signal-to-noise ratio of a mobile station belonging to a current base station (BTS). If RoT is available, the RoT is scheduled to meet the preset reference RoT level. If RoT is not available, the load is scheduled to meet the preset reference load level. For convenience of explanation, RoT is used here.

Accordingly, the scheduler of the base station determines whether to increase, decrease, or maintain the current data rate of the mobile station in consideration of the RoT, the buffer state and the power state of each mobile station.

1 is a view for explaining a connection configuration and operation method for controlling the mobile terminal in the system to date. As shown in FIG. 1, a BS (Bsae Station) includes a base transceiver system (BTS) and a base station controller (BSC). The base station manages its cell (s). The base station controller is connected to a plurality of base stations and controls each base station. In addition, as shown in FIG. 1, each mobile station is subject to reverse data rate control by a base station to which it belongs. Non-soft hand over (Non-SHO) mobile terminals receive reverse rate control only by their base stations, and mobile terminals in soft hand over (SHO) mode Reverse rate control is performed by a plurality of base stations that are active sets. The non-SHO mobile terminal refers to mobile terminals that are not in a handoff situation, and the SHO mobile terminal refers to mobile terminals in a handoff situation. Accordingly, in FIG. 1, the mobile terminals 111 and 113 belonging to one base station are controlled by one base station, and the other mobile terminal 112 is soft handover controlled simultaneously by the base station 1 101 and the base station 2 102. It becomes the mobile terminal in the state.

As described above, in the case of a mobile terminal controlled by a plurality of base stations, a reverse rate control message received from each base station may be differently received. This will be described with reference to FIG. 1 as a control process of a data rate. Base station 1 (101) and base station 2 (102) respectively transmits a rate control command to the mobile terminal according to its own RoT situation. In this case, the base station 1 101 may instruct the mobile terminal to lower the data rate, and the base station 2 102 may instruct the mobile terminal to increase the data rate. In this case, the mobile station follows the command of one of the base stations, and if the base station instructs any of the base stations to lower the data rate by Or-of-Down rule, the data rate is lowered. Because the scheduler of each base station determines the data rate of each terminal so as to maintain the reference RoT based on the received RoT. When the mobile terminal commanded to lower the data rate increases the data rate, the received RoT of the base station exceeds the reference RoT. Because it becomes.

Exceeding the reference RoT in a particular base station means that the interference level is increased, resulting in a decrease in throughput of the corresponding cell. Therefore, for the stability of the entire system, when the mobile station receives different rate control commands from a plurality of base stations, it checks whether there is any control command to lower the rate among the received control commands. If there is any control command to lower the transmission rate, the mobile station lowers the current transmission rate to perform data transmission.

However, there are some inefficiencies even when using Or-of-Down rules. The scheduler of the base station determines the data rate of each mobile station to maintain the received RoT as a reference RoT. However, when the mobile station, which has commanded the data rate to increase, lowers the rate, the received RoT of the base station is lower than the reference RoT. This does not fully utilize the available resources, which also degrades the throughput of the cell.

A situation similar to that described above also occurs when using Hybrid Auto Repeat and ReQuest (hereinafter, HARQ). This case will be described below. When the base station receives data in the reverse direction, the base station should transmit an ACK or NACK signal to the mobile terminal through an acknowledgment channel. However, in the case of a non-SHO mobile terminal, the corresponding base station may determine and transmit an ACK or NACK signal. However, in the case of a SHO mobile terminal, the situation received by each base station may be different. This will be described below with reference to FIG. 1. If the base station 1 101 successfully receives the packet transmitted by the mobile station 112, the base station 2 102 may fail to receive the packet transmitted by the mobile station. In this case, the base station 1 101 transmits the ACK signal to the mobile terminal, and the base station 2 102 transmits the NACK signal to the mobile terminal. Since the mobile station 112 receives the ACK signal indicating that the previous packet was successfully received from the base station 1 101, the mobile station 112 transmits the next packet. However, since the base station 2 102 has not successfully received the previous packet, that is, the NACK signal has been transmitted to the mobile station, it is expected that the previous packet will be retransmitted. In this case, signaling is required between the base station 1 101 and the base station 2 102 to confirm whether each cell has successfully received a packet. However, such signaling may act as an overhead. When the base station 1 101 transmits an ACK and the base station 2 102 transmits the NACK, the mobile station receives the ACK and transmits a new packet, but the base station 2 102 expects retransmission. Therefore, for more accurate operation, it is necessary to inform the signaling through the network that the base station 1 has transmitted the ACK to the base station 2.

Accordingly, an object of the present invention is to provide a traffic distribution control system and method suitable for a situation in order to increase the efficiency of a base station when controlling traffic in a base station and a base station controller in a mobile communication system.

Another object of the present invention is to provide a system and method for transmitting a consistent control message to a mobile terminal in a mobile communication system.

Another object of the present invention is to provide a system and method for efficiently controlling a mobile terminal in a handover situation.

It is still another object of the present invention to provide a system and method for improving throughput of a base station by transmitting a consistent control message to a mobile station when using a reverse hybrid automatic retransmission scheme.

A system of the present invention for achieving the above objects includes a plurality of mobile terminals and a plurality of base stations for communicating with the mobile terminals, wherein the base stations are a predetermined mobile in a mobile communication system connected to a base station controller. A system for controlling a handover of a terminal, comprising: a base station performing reverse rate control for a terminal that is not a handover situation in consideration of total reverse capacity and load of a handover mobile terminal, and an active set of the handover mobile terminal; And a base station controller for performing reverse rate control of the mobile station in consideration of the remaining capacity of the base stations communicating with the mobile station among the included base stations.

Method according to an embodiment of the present invention for achieving the above object,

A plurality of mobile terminals and a plurality of base stations for communicating with the mobile terminal, the base station is a reverse rate control method of the mobile terminal in a mobile communication system connected to the base station controller,

The base station is

Measuring a total reverse load of mobile terminals controlled by the base station and receiving a load of mobile terminals controlled by a base station controller from the base station controller, and measuring the measured total reverse load and a load received from the base station controller Using the reverse rate control for the mobile station instead of the handover situation,

The base station controller

When a specific mobile station needs handover, transmitting a reverse rate control stop message of the mobile station to a base station controlling the reverse rate of the mobile station; and among the base stations included in the active set of the mobile station. And performing reverse rate control of the mobile station in consideration of the remaining capacity of the base stations communicating with each other.

1 is a view for explaining a connection configuration and operation method for controlling the mobile terminal in the system to date;

2 is a block diagram illustrating control functions for explaining operations of a base station and a base station controller when controlling a traffic of a SHO mobile station and a non-SHO mobile terminal according to an embodiment of the present invention;

3 is a control flowchart of a handover of a mobile terminal in a control function unit of a base station according to an embodiment of the present invention;

4 is a control flowchart of handover of a mobile terminal in a control function unit of a base station controller according to an exemplary embodiment of the present invention.

5 is an internal block diagram of a base station apparatus and a base station controller apparatus according to a preferred embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings.

In addition, in the following description, there are many specific details such as specific messages or signals, which are provided to aid the overall understanding of the present invention, and it is understood that the present invention may be practiced without these specific details. It will be self-evident to those of ordinary knowledge. In the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the present invention, the base station controller performs data rate control differently according to a situation of soft handover and a situation of no soft handover. That is, the control function of the SHO mobile terminal is in charge of the base station controller, and the control function of the non-SHO mobile terminal is in charge of the base station. In addition, the following items will be described based on the rate control. However, not only the rate control but also the control of the response signal may be performed. Collectively, this is called a reverse control message. The reverse control message is divided into a case of transmitting a rate control bit (RCB), which is a reverse rate control bit, and a case of transmitting a grant message. In case of transmitting the reverse rate control bit, the reverse rate control bit may indicate an increase / decrease / maintenance at the current rate, or may indicate only an increase / decrease. On the other hand, in case of using the acknowledgment message, the mobile station can transmit a command to perform reverse transmission at a certain rate in the reverse direction from the next slot. For example, if a mobile station performing reverse transmission receives an acknowledgment message that allows transmission at 38.4 kbps while performing reverse transmission at 9.6 kbps, the mobile terminal can perform transmission at 38.4 kbps after skipping 19.6 kbps. will be. In the following description, the reverse rate control will focus on the case of using the RCB. However, the same may be applied to the case of using the approval message.

In addition, the reverse control message may include a response signal. First, the response signal is as follows. The base station controller may receive different decoding results for packets transmitted by the SOH mobile station from different base stations. That is, a specific base station may indicate good reception, and a message received from another base station may indicate a case of poor reception. The base station controller transmits an ACK, which is a response signal indicating good reception, to the SHO terminal by using the messages received from the two base stations. Such embodiments will be described below.

FIG. 2 is a block diagram of control functions for explaining operations of a base station and a base station controller when controlling a transmission rate of a SHO mobile station and a non-SHO mobile terminal according to an exemplary embodiment of the present invention. Hereinafter, the control functions and other functions of the base station and the base station controller when controlling the transmission rate of the SHO mobile terminal and the non-SHO mobile terminal according to the present invention will be described in detail with reference to FIG. 2.

Each reverse control function 201, ..., 20N of the base stations performs reverse rate control of the Non-SHO mobile terminal. This control performs the same control as in the general case of controlling the mobile station in the base station to date. Accordingly, signaling, call allocation, etc., for the non-SHO mobile station are performed through the base station controller as in the conventional scheme. However, the control functions 201, 20N, 20N of the base stations according to the present invention do not perform reverse rate control for the SHO mobile terminal. In addition, the control function unit 210 of the base station controller performs control on the base stations that have been performed so far. In addition to this, the control function unit 210 of the base station controller performs reverse rate control of the SHO mobile terminal according to the present invention. That is, control is performed according to transmission rate control of the SHO mobile terminal and transmission of a signal transmitted through the response channel.

Then, when the mobile terminal proceeds from the state where the handover is not necessary to the handover state, the control according to each state of each of the control function units 201, ..., 20N of the base stations and the control function unit 210 of the base station controller is performed. Take a look at

The control function unit 201 of the base station allows the mobile station to receive reverse rate control only from the base station when the mobile terminal does not need handover, that is, if it is included in only one base station. That is, it generates a rate control information bit and a response bit to transmit to the terminal. In addition, various control such as call call, call, signaling, rate control, and ACK / NACK reception of a received signal are performed in the base station controller.

However, when the mobile terminal changes to a situation in which a soft handover is required, the control function unit 201 of the base station controller sends information on the handover time and the active set of the mobile terminal to the mobile terminal. Create In addition, since the control function 210 of the base station controller is performed at the base station controller, the control function 210 checks whether an allocation of a new rate control channel is necessary. At the same time, it is checked whether an allocation of an ACK channel is necessary. When new channels are needed according to the test result, the control function unit 210 of the base station controller generates new rate control channel information and new response channel information to the mobile station. The control function unit 201 of the base station cannot know the state of another base station. Therefore, the control function unit 210 of the base station controller determines whether to allocate a new channel, and when a new channel is required, the control function unit 210 of the base station controller controls the base station and transitions to the SHO state. Set the channel. In detail, the base station constructs a message of handover time information, active set information, and new channel allocation information received from the control function unit 210 of the base station controller and transmits the message to the mobile station. Accordingly, a new channel according to the present invention is allocated between the base station and the mobile terminal.

Next, the control when the handover is terminated because the mobile terminal in the handover situation belongs to a specific base station. The control function unit 210 of the base station controller is configured to control each of the base station control functions 201,..., Which the mobile terminal belongs to when the mobile terminal performing the handover enters a specific base station, that is, when the handover ends. 20N) to individually perform reverse rate control of the mobile terminal. Let's look at these cases.

When the mobile station receives the reverse rate control from the function control unit 210 of the base station controller and when the mobile station is controlled by the base station, the delay time for transmitting the control message to the mobile station is different. When the terminal receives the reverse rate control information from the base station controller, a delay of about 2 frames occurs. Herein, a frame is a transmission unit of data of rate control information transmitted through a forward rate control channel. Therefore, when the reverse rate control of the mobile station from the base station controller may cause a problem in the transmission of the ACK / NACK signal transmitted on the response channel. For example, assuming that the base station generates and transmits the ACK / NACK signal of the signal received from the mobile station within 2 frames (or 1 frame), the NACK signal is received for the data received at the current time point (1). When transmitting to the mobile terminal (2 time points), the mobile terminal receives the NACK signal and retransmits the corresponding frame at 3 time points. Such time points 1, 2 and 3 are time points which occur sequentially. Therefore, each of the time points may be a transmission time in the air state, or may be a time until the received information is confirmed after the error checking is performed on the received frame.

However, since the mobile station which is performing the handover is controlled by the reverse rate from the base station controller, more delay time occurs than the base station processes. In detail, the signal transmitted from the mobile station to the base station is transmitted to the base station controller, and a NACK signal is generated from the base station controller for the corresponding signal, and a delay of at least 1 frame occurs to be transmitted to the mobile terminal through the base station. do. That is, when a base station controller generates a NACK signal and transmits the received signal transmitted one frame before the current time point 1 to the mobile station, the mobile station retransmits the frame at three time points. In this case, when the handover ends, the base station controller transmits an ACK / NACK signal to the mobile station for the immediately previous frame, and the base station performs the rate control of the mobile station from the time point when the handover ends. Therefore, when the base station controller transmits an ACK / NACK signal for a frame received at a previous time to the mobile station, the base station may transmit an ACK / NACK signal for the received frame after the handover is terminated. In this case, the mobile station receives a retransmission request for different data and causes a collision between the ACK / NACK signal received from the base station controller and the ACK / NACK signal received from the base station.

In general, when the mobile station is controlled by the base station controller, the delay time of the control message is longer than when the base station is controlled by the base station. Therefore, as the mobile station switches from the non-SHO state to the SHO state, the time point for transmitting the ACK / NACK signal becomes longer. In this case, there is no problem in whether the mobile station allocates a new channel or uses an existing channel to transmit an ACK / NACK signal. However, when switching from the SHO state to the non-SHO situation, it becomes shorter at the time of transmission of the ACK / NACK signal. Therefore, if the existing channel is used as it is, there is a problem that the base station and the mobile station may need to transmit the ACK / NACK signal for two packets at the same time.

Therefore, in this case, the present invention can be configured to stop the packet transmission by the difference between the ACK / NACK signal transmission time between the base station and the base station controller. Alternatively, when the transition from the non-SHO state to the SHO state, the base station allocates a new response channel to the mobile station. Through this, the response signal during the control from the base station controller may be transmitted to the assigned response channel when controlled by the base station controller, and may be configured to transmit the response signal for the new packet to the newly allocated response channel from the current base station. In the case of using the second method, the mobile station has two response channels for the transmission delay time between the base station and the base station control period, and the base station must maintain a state in which two response channels are allocated to the mobile station.

Next, the operation of the control function unit 210 of the base station controller performing the operation according to the above two embodiments of the present invention will be described. The control function unit 210 of the base station controller performs a general control function. When the mobile terminal is in a handover situation according to the present invention, the control function unit 210 of the base station controller determines whether a new channel is allocated to the mobile terminal in the handover situation from the control function unit 201 of the base station. When the inquiry is received, the handover is made and the state of the target base stations to receive the call is examined, and the information about this is transferred to the inquired base station. In addition, if the reverse rate control is required for the mobile station in the handover situation from the control function unit 201 of the base station, the mobile station performs the rate control in consideration of the resource state of the base stations. Then, the packet received from the mobile terminal through the source base station to hand over the call in progress and the target base station to transfer the call to detect the good or bad reception of the packet received through the symbol combining. When the received packet is good, the control function unit 210 of the base station controller transmits an ACK signal through a response channel established between each base station and the mobile station that is performing the handover, and handover when the received packet is bad. The NACK signal is transmitted through a response channel established between each base station and a mobile station that is being performed.

Then, when the handover of the mobile station is completed, the control function unit 210 of the base station controller transmits an ACK / NACK signal for the packet received from the mobile station to the mobile station through a channel established during the handover. In the first case, the base station is controlled to stop the reverse data transmission for a predetermined time between the base station and the mobile station. In contrast, in the second embodiment, the ACK / NACK is transmitted through a separate channel instead of the channel where the handover is being performed on the channel for transmitting the ACK / NACK between the mobile station and the base station. After transmitting the ACK signal for the last frame received by the base station controller, the channel is released. However, the channel transmitting the ACK / NACK signal set between the base station controlling the current mobile station and the mobile station is maintained. Instructing the control function unit 201 of the base station to perform reverse rate control for the mobile terminal in which the handover is completed.

As described above, when the base station controller controls the transmission rate of the SHO mobile station, the base station subtracts the transmission rate of the mobile station from the total capacity, and the transmission rate of the mobile stations in its area based on RoT or load in the remaining capacity. Since the control is to have the advantage that can increase the throughput (Throughput) of the base station. In addition, since the different base stations do not transmit different response signals to the SHO mobile terminal, the efficiency of the base station can be increased, and the mobile terminal can be easily controlled.

By controlling the SHO mobile terminal in the base station controller, the mobile terminal is not controlled differently by the plurality of base stations included in the active set, and receives the same signal from the plurality of base stations by the base station controller. Through this, signal reception probability of packet data and response channel can be increased.

3 is a control flowchart of handover of a mobile terminal in a control function unit of a base station according to an exemplary embodiment of the present invention. Hereinafter, a control process upon handover of a mobile station performed by a control function unit of a base station according to the present invention will be described in detail with reference to FIG. 3.

The control function unit 201 of the base station measures the overall RoT or load of the base station in step 300. At this time, the entire RoT can be performed at a predetermined time, and the load can be calculated by the base station for the current reverse link state. Accordingly, when the load is used, the control function unit 201 of the base station continuously measures the load. When the control is performed based on the RoT, the control function 201 measures the RoT every predetermined time.

When the RoT measurement is completed or the load calculation is completed as described above, the control function unit 201 of the base station proceeds to step 302. The control function unit 201 of the base station receives the reverse load of the mobile terminal controlled by the base station controller because the handover is in progress in step 302. Since this is a value received from the base station controller, it is information that the base station controller informs the base station at a specific period or always. Therefore, the base station receives this in step 302, and proceeds to step 304 to perform the reverse load of the mobile terminals that are not the handover situation, i.e., the mobile station whose reverse rate is controlled by the control function unit 201 of the base station according to the present invention. Calculate

Thereafter, the control function unit 201 of the base station proceeds to step 306. The control function unit 201 of the base station calculates the capacity of the currently available reverse link from the values checked in steps 300 to 304. In addition, the reverse rate control of the mobile stations is performed not in the handover situation controlled by the base station according to the currently available reverse link. In addition, the control function unit 201 of the base station transmits an acknowledgment signal (ACK / NACK) to the packet data received in the reverse direction from the mobile terminal in step 306. After performing such control, the control function unit 201 of the base station proceeds to step 308 and checks whether a message indicating that a handover situation has occurred is received from the base station controller for the mobile terminal controlled by the base station. If there is a mobile terminal in which a handover situation occurs in step 308, the control function unit 201 of the base station proceeds to step 310 to exclude the corresponding mobile terminal from the mobile stations under reverse rate control. That is, reverse rate control by the base station is stopped. Then go back to step 300 to measure RoT or load. In this case, if the RoT-based operation is not a predetermined RoT measurement time, the process proceeds to step 302 without performing this operation. The reverse rate control can be quickly performed for the terminal that communicates only with the base station.

Meanwhile, although not shown in FIG. 3, when a call of a specific terminal controlled by a base station controller enters a predetermined base station, a reverse rate control may be performed for the terminal. In this case, the base station measures RoT or Load including the corresponding terminal during RoT measurement or load measurement in step 300, and performs reverse rate control including the terminal. In addition, a time point for the rate control may use a separate channel as described above, or may use a method of stopping backward transmission for a predetermined time.

4 is a control flowchart of handover of a mobile terminal in a control function unit of a base station controller according to an exemplary embodiment of the present invention. Hereinafter, with reference to Figure 4 will be described in detail the control process at the time of handover of the mobile terminal performed in the control function of the base station controller according to the present invention.

The control function unit 210 of the base station controller maintains the call control state in step 400. In this case, the call control state refers to control according to call allocation and transmission of a control message through a base station, and does not include reverse rate control for a mobile station other than a handover state according to the present invention. For such mobile terminals, reverse rate control is performed at the base station as shown in FIG. Maintaining the call control state as described above, the control function unit 210 of the base station controller proceeds to step 402 and checks whether a specific terminal moves to generate a mobile terminal requiring handover. If a mobile terminal requiring handover occurs as a result of the check in step 402, the control function unit 210 of the base station controller proceeds to step 404, and otherwise proceeds to step 400.

In step 402 to step 404, the control function unit 210 of the base station controller transmits the call transfer message to the base station. That is, a message for stopping control of the reverse rate for the mobile station controlled by the base station is transmitted to the corresponding base station. In operation 404, the control function unit 210 of the base station controller determines an active set and a handover time of the mobile terminal to perform the handover. After performing the above step 404, the control function unit 210 of the base station controller proceeds to step 406 to newly transmit a reverse rate control channel and a channel for transmitting a response signal (ACK / NACK) to the mobile station to perform the handover. Check if it needs to be allocated. If it is necessary to allocate a new channel as a result of the check in step 406, the control function unit 210 of the base station controller proceeds to step 408, and otherwise proceeds to step 410.

In step 408, the control function unit 210 of the base station controller allocates a new channel to the mobile station to perform the handover, and communicates with the mobile station to inform the mobile station of the newly allocated channel. The channel assignment message is transmitted via.

Then, the control function unit 210 of the base station controller proceeds to step 410 for the mobile station to perform the handover state of the base stations that communicate with the mobile terminal among the base stations included in the active set of the mobile terminal In consideration of this, the reverse rate of the mobile station is controlled. In this case, the response signal received from the mobile station is also transmitted to the base station controller without being processed by the base station. Accordingly, the control function unit 210 of the base station controller may retransmit data or transmit new data using information received from the mobile station.

As such, since the base station controller controls the mobile terminal in the handover situation, the mobile terminal can receive a uniform response signal, and the same message can be received.

The control function unit 210 of the base station controller performs a rate control on the reverse link of a specific mobile terminal as in step 410, and proceeds to step 412 to check whether the handover situation of the mobile terminal in the handover state is terminated. do. In other words, it checks whether only one base station communicates with a specific base station. When the handover situation is terminated in step 412, the control function unit 210 of the base station controller generates a control transfer message instructing to perform reverse rate control to the base station where the mobile station is located in step 414. , Pass it. Therefore, when the handover situation of the mobile station is terminated, transmission control of the reverse rate and the response signal is transferred to the base station by the specific base station again. The control function unit 210 of the base station controller proceeds to step 400 after performing step 414 as described above.

Next, the connection relationship between the base station apparatus and the base station controller apparatus and its internal configuration will be described. 5 is an internal block diagram of a base station apparatus and a base station controller apparatus according to a preferred embodiment of the present invention.

In FIG. 5, reference numeral 510 denotes an internal block diagram of a base station controller, and reference numeral 520 denotes an internal block diagram of a base station. It should be noted that FIG. 5 illustrates only parts necessary for describing the present invention. First, the internal configuration and operation of the base station controller 510 will be described first.

The controller 511 of the base station controller 510 includes a salping control function 210 in FIG. 2. Therefore, the control according to the present invention is performed. Therefore, the data required by the controller 511 is stored in the memory 512. That is, the memory 512 stores data for performing the control process as shown in FIG. 4. In addition, it stores various data for controlling the mobile terminal performing the handover. Accordingly, the controller 511 generates a message for controlling the mobile terminal or controls the base station to control generation of a message to be transmitted to the mobile terminal. The data processor 514 divides forward data to be transmitted to a specific mobile terminal into a size to be transmitted or combines the data received from the mobile terminal to deliver the data to a higher level. The interface 513 refers to an apparatus for performing an interface between a base station and data transmitted / received during a base station control period.

Next, a block configuration included in the base station 520 and its operation will be described. The base station 520 includes an interface 522 for performing an interface of data received from the base station controller 510. It also includes a control unit 521 for performing the control according to the present invention. The controller 521 includes the reverse control function described above with reference to FIG. 2. Accordingly, the controller 521 performs backward control only on the mobile terminal that does not perform handover. In addition, even when the reverse control is performed by the base station controller 510, since the message is actually transmitted from the base station to the mobile terminal, the base station controller 510 generates and processes when a control message transmission to the mobile terminal being handed over is required. However, the base station controller 510 may be configured to directly generate and transmit such a message.

The switch 523 performs a switching connection operation for transferring the data received from the forward data or the reverse direction to each mobile terminal to the interface 522 or the data received from the controller 521 to the base station controller 510. Perform. The switch may be configured as a dedicated line in some cases, but is generally configured as a switch. Data for transmission to a particular mobile terminal is processed by modem 524 and radio 525. The processed data is transmitted to the mobile terminal through the antenna. The modem 524 and the radio unit 525 are elements configured to correspond to the mobile terminal, respectively. The modem 524 encodes and modulates data to be transmitted in the forward direction, and demodulates, decodes and outputs the data received in the reverse direction. The wireless unit 525 performs band up conversion and power amplification for transmission to the corresponding mobile terminal, and outputs the baseband signal by performing low noise amplification and band down conversion on the data received in the reverse direction. Since the control operation performed by the base station 520 and the base station controller 510 having the above configuration at the time of handover of the mobile terminal is as described above, it will not be further described herein. The modem 524 and the wireless unit 525 of FIG. 5 become a "packet transmitting / receiving unit".

As described above, when the base station controller divides and controls the reverse traffic by dividing into a mobile terminal which performs a handover and a mobile terminal that is not, there is an advantage that the same control information can be transmitted to the mobile terminal. In addition, there is an advantage that it is easy to transmit the signal for the rate control and complex automatic retransmission of the mobile terminal performing the handover. In addition, the mobile station that does not perform the handover has the advantage that the rate control can be quickly enabled by performing the reverse rate control in the base station (BTS).

Claims (55)

A mobile terminal and a base station controller connected to the first and second base stations in a handover area commonly occupied by a first base station, a second base station adjacent to the first base station, and the first and second base stations. In the mobile communication system comprising the base station controller to control the mobile terminal, Detecting a mobile terminal in a handover state; Generating a reverse control message for a specific mobile terminal in a handover state; Transmitting the generated reverse control message to the first and / or second base station. The method of claim 1, wherein the reverse control message, The method of claim 1, wherein the rate control message for the mobile terminal. The transmission rate control message of claim 2, The message characterized in that the message indicating the increase or decrease with respect to the transmission rate of the mobile terminal. The transmission rate control message of claim 2, The message characterized in that the message indicating the increase, decrease or maintenance of the transmission rate of the mobile terminal. The transmission rate control message of claim 2, The method characterized in that the generated in consideration of the thermal noise (RoT) of the base stations. The transmission rate control message of claim 2, And receiving status information of the buffer of the mobile terminal and generating the buffer according to the reported status information of the buffer. The transmission rate control message of claim 2, And generating the power in consideration of the transmittable power of the mobile terminal. The method of claim 1, wherein the reverse control message, The method as ACK / NACK message to the packet received from the mobile terminal. The method of claim 8, And generating and transmitting an ACK message when the packet data received from one of the base stations is good for the packet data transmitted by the mobile station in the reverse direction. The method of claim 1, wherein the reverse control message, The information message indicating a reverse rate of the mobile terminal. The method of claim 10, wherein the reverse rate information message, And a grant message indicating a reverse rate of one of a set having a plurality of reverse rates for the mobile terminal. The method of claim 10, wherein the reverse control message, The method characterized in that the generated in consideration of the thermal noise (RoT) of the base stations. The method of claim 10, wherein the rate control message, The method as claimed in claim 1, wherein the information is generated according to the state information of the buffer reported from the mobile terminal. The method of claim 10, wherein the rate control message, And generating the power in consideration of the transmittable power of the mobile terminal. The method of claim 1, And transmitting a message requesting the transfer of control to the mobile terminal together with the reverse control message to the base station. The method of claim 15, The message for requesting the transfer of control to the mobile terminal includes control point information of the base station. The method of claim 1, And when a handover of the mobile terminal ends, transmitting a message for transferring control of the mobile terminal to a base station including the mobile terminal. The method of claim 17, And ending the reverse transmission for a predetermined time to a base station in which the mobile terminal is included, when the handover of the mobile terminal is terminated. The method of claim 1, And transmitting information to the base stations in the reverse rate control message to stop the control of the mobile terminal. A mobile terminal and a base station controller connected to the first and second base stations in a handover area commonly occupied by a first base station, a second base station adjacent to the first base station, and the first and second base stations. In the mobile communication system comprising the base station controller to control the mobile terminal, A base station controller which determines whether a handover situation of the mobile stations is determined and transmits a reverse control message of each mobile station to the mobile stations which are the handover situation; And a base station transmitting a reverse control message for the mobile station instead of the handover situation. The method of claim 20, wherein the reverse control message, And a reverse rate control message for the mobile terminal. The method of claim 21, wherein the reverse rate control information, The system is generated in consideration of the power state, the buffer state and the throughput of the mobile terminal. The method of claim 20, wherein the reverse control message, And a response signal (ACK / NACK) message for packet data received from the mobile terminal through the base stations. The method of claim 20, wherein the reverse control message, And a grant message indicating one reverse rate among a set having a plurality of reverse rates for the mobile terminal. The method of claim 24, wherein the grant message indicating the reverse rate, The system is generated in consideration of the power state, the buffer state and the throughput of the mobile terminal. The method of claim 20, wherein the base station controller, When a handover situation occurs in any one of the mobile stations controlled backward by the base station connected to the base station controller, the base station stops the reverse control for the mobile terminal, and further performs the reverse control for the mobile terminal. The system described above. The method of claim 26, wherein the base station, And stopping reverse control of the mobile station when receiving a reverse handover stop message from the base station controller. The method of claim 20, wherein the base station controller, And when the handover situation of the mobile terminal is terminated, forwarding a reverse control request message of the mobile terminal to the base station where the mobile terminal is located. The method of claim 28, wherein the base station, The system characterized in that for performing a reverse control for the mobile terminal after waiting for a predetermined time when receiving a reverse control request message of a specific mobile terminal. The method of claim 29, wherein during the predetermined predetermined time, And the transmission delay time of the traffic and control signals from the base station controller to the mobile terminal. The method of claim 28, wherein the base station, And when a reverse control request message of a specific mobile station is received, a new channel is allocated to the mobile station to perform reverse rate control for the mobile station. The method of claim 20, wherein the base station, And generating a reverse control message for the mobile station rather than the handover situation and transmitting the reverse control message to the mobile station. The method of claim 32, wherein the reverse control message, The system is generated in consideration of the power state, the buffer state and the throughput of the mobile terminal. A mobile terminal and a base station controller connected to the first and second base stations in a handover area commonly occupied by a first base station, a second base station adjacent to the first base station, and the first and second base stations. In the mobile communication system comprising the base station to control the mobile terminal, Measuring a total reverse load of mobile terminals controlled by the base station and receiving a load of mobile terminals controlled by a base station controller from the base station controller; And performing reverse control on a mobile terminal rather than a handover situation by using the measured total reverse load and the load received from the base station controller. The method of claim 34, wherein the reverse control, The system characterized in that the reverse rate control for the mobile terminal rather than the handover situation. 36. The method of claim 35, wherein the reverse rate control, The system is performed in consideration of a power state, a buffer state and a throughput of the mobile terminal. The method of claim 34, wherein the reverse control, The control system characterized in that the control of the response signal (ACK / NACK) for the packet data received from the mobile terminal through the base stations. The method of claim 34, wherein the reverse control, And transmitting a grant message indicating a reverse rate of one of a set having a plurality of reverse rates for the mobile terminal. 39. The method of claim 38, wherein the grant message indicating the reverse rate, The system is generated in consideration of the power state, the buffer state and the throughput of the mobile terminal. The method of claim 34, wherein And receiving a reverse control request message for a specific mobile station from the base station controller to perform reverse control on the mobile station, not the handover situation in the base station, including the mobile station. 36. The method of claim 35 wherein The reverse rate control for the mobile station receiving the reverse rate control request message from the base station controller performs the reverse rate control for the mobile station after waiting for a predetermined time. The method according to claim 41, wherein during the predetermined predetermined time, The transmission delay time of traffic and control signals from the base station controller to the mobile station. 36. The method of claim 35 wherein When receiving a reverse rate control message from the base station controller, assigning a new channel to the mobile station to perform reverse rate control for the mobile station. A mobile terminal and a base station controller connected to the first and second base stations in a handover area commonly occupied by a first base station, a second base station adjacent to the first base station, and the first and second base stations. An apparatus for controlling the mobile terminal in the base station controller in a mobile communication system comprising: A memory for storing information of a mobile terminal and load information of each base station from each base station; And a control unit for generating a reverse control message using the reverse load of each base station and the information of the mobile terminal stored in the memory when the handover of the mobile terminal is detected and receiving the reverse control request message from the base station, and outputting the reverse control message to the base stations. The device, characterized in that. 45. The method of claim 44, wherein the reverse control message is And the reverse rate control (RC) message of the mobile terminal. 45. The method of claim 44, wherein the reverse control message is The device characterized in that the ACK / NACK signal for the packet transmitted by the mobile terminal in the reverse direction. The method of claim 44, wherein the information of the mobile terminal, And the transmission power information of the mobile terminal and / or buffer information stored in the mobile terminal. The method of claim 44, The apparatus of claim 1, further comprising an interface unit for transmitting the output of the control unit to the base stations. A mobile terminal and a base station controller connected to the first and second base stations in a handover area commonly occupied by a first base station, a second base station adjacent to the first base station, and the first and second base stations. An apparatus for controlling the mobile terminal at the base station in a mobile communication system comprising: A packet transceiver for transmitting / receiving packet data with a mobile terminal and transmitting a reverse control message accordingly; A switch for switching for transmission of data to be transmitted to the mobile terminal, a message to be transmitted to the base station controller and a control message received from the base station controller; A control unit for measuring a reverse load of the base station using the packet transceiver, calculating a load on the mobile terminal in a handover situation received from the base station controller, and performing a reverse control on the mobile terminal instead of the handover situation; Said device characterized in that it comprises a. The method of claim 49, wherein the control unit, And receiving a reverse control message to be transmitted from the base station controller to the mobile terminal in a handover situation, controlling the packet transceiver to transmit a reverse control message to the mobile terminal. The method of claim 50, wherein the reverse control message, And a reverse rate control (RC) message transmitted to the mobile terminal in the handover situation. The method of claim 50, wherein the reverse control message, The device characterized in that the ACK / NACK signal transmitted to the mobile terminal in the handover situation. The method of claim 49, wherein the control unit, And when the control of the mobile terminal having handover is completed from the base station controller includes performing the reverse control by including the mobile terminal in the mobile terminal instead of the handover situation. The method of claim 53, wherein the control unit, And generating a message for requesting stopping of reverse transmission for a predetermined time for the control of the mobile terminal in which the handover is completed and transmitting the message through the packet transceiver. The method of claim 53, wherein the control unit, The apparatus as claimed in claim 1, wherein a reverse control is performed by setting a separate control channel for controlling the mobile terminal in which the handover is completed.